1. Field of the Invention
The present invention relates to ventilation systems for busses, and, more particularly, to a duct system for delivering heated and air conditioned air evenly to all of the seating areas in a bus.
2. Description of the Problem
Busses, particularly school busses, have often been equipped with primitive heating, ventilation and air conditioning systems. Typically free air systems have been used which result in highly uneven temperatures through the vehicle""s passenger compartment. In some applications overhead ducts have been used which provide better air distribution, but this results in reduced head room. Aircraft type high pressure systems have also been employed in busses with good results, but these can entail such expense as to be difficult to justify for school busses.
Under floor duct and vent systems have been proposed for smaller vehicles such as vans and cars as disclosed in U.S. Pat. Nos. 4,413,550 to Piano and 6,068,046 to Pommier et al. These systems do not however deal with the extensive lengths encountered in constructing a duct system for a bus fed from one or more air treatment units.
According to the invention there is provided an air distribution mechanism for a bus comprising an air blower and ducts connected to the air blower which extend along the interior side of the body side walls of the bus for transporting the air from the blower to various parts of the bus. Distributed along the length of the body side ducts and mutually spaced from one another are a plurality of underseat ducts connected to and extending from the body side ducts into the interior of the vehicle. Vents release air from the underseat ducts into the passenger compartment of the vehicle. The body side ducts expand in cross sectional area as distance from point of the connection each body side duct with the air blower increases. Reducing resistance to air flow in the primary air channel as a function of distance from the air blower results in the amount of air released from each vent being about the same.
Additional effects, features and advantages will be apparent in the written description that follows.